Apparatus for applying a cement coating



Jan. 25, 1955 R. .1. HARRINGTON ET AL 2,700,535

APPARATUS FOR APPLYING'A CEMENTCOATING Filed June 29, 1951 4Sheets-Sheet l fans wen awm flffarneys 1955 R. J. HARRINGTON ETAL2,700,535

APPARATUS FOR APPLYING A CEMENT COATING 4 Sheets-Sheet 2 Filed June 29,1951 m f w e m 1 Jan. 25, 1955 R. J. HARRINGTON EIAL 2,700,535

APPARATUS 0P APPLYING A CEMENT COATING 4 Sheets-Sheet 3 Filed June 29,1951 lnz'enfa s MM 6? flff'orneys' 1955 R. .1. HARRINGTON ETAL 2,700,535

APPARATUS FOR APPLYING A CEMENT COATING Filed June 29, 1951 4Sheets-Sheet 4 A A A A A A A IA A l? 5 73 39 35 4'7 3/ ,3 3 42 40 I I J---L A\ 63 30 I: 11 .j a5

65 A 4 63a 37 l 36 O I [2+ 636 +2 1 I I I l 1 I n 1 I United StatesPatent C) -APPARATUS FOR APPLYING A CEMENT COATING .Russell J.Harrington and Richard P. Harrington, Rockford, Ill.

-Application-June $29, 1951, Serial No. 234,338

.20.Claims. (Cl. 259-451) apparatus for applying automatically mix thecement stream and a stream of .water in desired proportions, and toapply the wetcement mixture by pneumatic pressure onto the surfacedesired to bencoated.

- It is alsoan object .of this invention to spray a wet mixture ofcementonto the surface desired to' be coated by means adjustable tocontrol the proportions of the ingredients and the texture of thecoating. Another object of this invention is to provide a spray .gunfor, mixing water and dry cement and for discharging the resulting wetmixture, and-operated-without undue :strain on the operator.

A further object of this invention is to provide a unitary controlmeansfor controlling the flow of dry cement aggregate and the-flow of waterto the spray gun.

means for insuring. a smooth and even flow of" finely divided dry cementaggregate to thespraygun.

Other? and further objects and advantages of the invention will become:apparent from a consideration of which may' 'be' manually held A stillfurther-ob ect'of this invention is toprovide the following descriptionof a preferredembodiment thereof. 1n the-drawings:

Figure l is aperspective .view showing the operator applying a cementcoating-in accordance with thepresent invention and showingthe-transportable: assembly of the i cement, air'and water sources, andcontrols therefor, employed in the present invention.

. Fig. ,2 is aperspective'viewof the-spray gun for applying the wetspraycoating of cement, including the mixing valve for mixing thestreams of dry cement-and water at the 'dischargeanozzle.

'.Fig. 3 isanother-pcrspective view of the spray gun, taken from theopposite side from the view :of-zFig. 2. Fig. 4 illustrates theharnessand --breathingmask worn by the --operator.

Fig. 5 is a front view, with certainof the-parts omitted for -clearness,of the :transportable assembly of dry cement, air and water'sources,accordingto the present invention. Fig. 6 is a rear View of theassembly'of Fig. 5.

Fig. 7 is an end view'of the assembly'of'Figs. 5 and 6.

Fig. 8 is a section illustrating the conduits,'valves and controlmechanism 'which'govern the supply of dry cement aggregate, air'andwater from the unitary. transportable assembly thereof.

Fig. 9 is a vertical section transversely .alon'g the middle of Fig. 8,viewing toward the left .therein, illustrating particularly the valvecontrolling the flow of dry aggregate to the discharge nozzle.

I, .Fig. 10 is a top vview in section of the Fig. 9 structure.

Fig. 1-1 isa section along theline -1111.of Fig-l 10 illustrating themechanism controlling a valve whichcontrols, the flow of air into.vthecement valve.

l2. is -a section zalong. the line IZ-12 ofFig. 10

' explained hereinafter.

2 illustrating the mechanism controlling a'valve which controls the flowof water to the discharge nozzle. v

Fig. 13 is a's'ection along the line 1-3-13 of Fig. 10 illustrating themechanism controlling a valve which controls the flowof'agitating airinto the tank 'ofa'ggregate.

Fig. '14 is a section along the line 1414 of Fig. v10 illustratingthe'positions in the aggregate tank of the cement valve and ofthe'conduit for dischargingagitating air into the tank.

'In accordance with the presentinvention, a'tru'ck 10 is provided with arearwardly extending frame :11 adapted to support the components of theinvention, so that the entire'assembly is readily transportable toandfrom the job. An air storage tank '12 is connected to receive andcontain air under pressure from an air compressor 13. 'A- water tank14is also supported by the-truck frame, as is an-upright cylindricaltank15 which contains an aggregate-of dry sand and cement, to be ultimatelymixed with water and the resulting wet mixture sprayed-onto the surfaceto be coated, in the manner A ladder '16 on the truck frame permits theoperator to have ready access to manual shut-off valves "adjacent the:compressed air tankand the-water tank, allof these valves -beinggrouped above a horizontal platform 17-which extends over the watertank. Access -to the aggregate tank 15 may *be had through a-detachabletop closure 18.

One outlet conduit 19' from the air tank-12 is connected to communicatewith the aggregate tank, for a purpose which will be apparenthereinafter. A manual shut-ofi valve-20'controls the supply of air toconduit 19. p

Another outlet conduit 21 from air tank 1'2 connects with-a fitting 22which communicates through pipe 23 to the top of the water tank. Thus, aportion of'the compressed air from-tank 12 is used to keep the water intank 14 under pressure and thereby insures the desired water flowtherefrom. Manual valve 24 controls the pressurized air supply to thewatertank. -The"water flow from tank 14 flows past outlet valve 26.-Valve 25 is a reliase valve for releasing air from the top "of the"water tan Air compressor 13 is provided witha pipe 13acommunicatingwith an exhaust outlet 13b leading to the atmosphere. Suitable valvemeans may-be provided for selectively directing this exhaust from theair compressor into-a conduit 14a which extends into thewater tank 14 atthe bottom thereof to form aloop therein and terminates in an exhaustpipe 14b communicating with the atmosphere. Inthis-manner, the waterwithin water tank 14 may be heated to avoid freezing thereof during coldweather.

As best seen in Figs. 8 and 10 the air conduit 19 leads from air tank 12through a swivel connection 19a to a coupling 27 having two outletconduits,.28 and.29. Conduit 28 in turn connects with another coupling30 having two outlet conduits, 31 and 32. Conduit 31 leads through valve33 to a U-shaped horizontal conduit 34which is disposed within theaggregate tank adjacent the bottom thereof. At its inner side conduit 34is formed-with a plurality of openings 35 through which feed air escapesto exert an upward and centrally directed force against the sand-andcement in tank 15 and to agitate andmix the same. At its other endfeedair tube 34 is provided with a closure cap 36, so that the entiresupplyof air to tube 34 is dissipated within the aggregate-tamer Cap 36is-readily removable from conduit 34 to permit-cleaning out of thelatter.

Conduit 32 leads through valve 37 to a drive'air conduit 38 which isopen at its free'end. The freeend of eductor conduit 38 is disposedwithin a tubular assembly,

generally indicated at 39, a portion of which is'disposed within theaggregate'tank 15- near the bottom thereof and above the agitatorconduit 34 centrally located with re spect thereto. The tubular assembly39'includes a fixedly positioned inner tube 40 formed with an elongatedslot 41 extending lengthwise along its bottom'portion." An

outer tube 42 is snugly rotatably disposed about tube 40 and is formedwith an elongated slot 43 adapted to register with the slot 41in tube40. When the slots 41 "and 43 are in register'the cement aggregate ispermitted to enter from the tank 15 into inner tube 40-and flow therein3 in the direction of the air stream from drive air conduit 38. Sincethe slots 41 and 43 must be in register for such flow of the aggregateto take place, it will be seen that the tubular assembly 39 forms asleeve valve controlling the flow of the aggregate from tank into tube40.

Disposed at the front of aggregate tank 15 is a lever 44 fixedly securedby a collar 44:: to the outer tube 42 of the sleeve valve and thusadapted by its angular position to control the alignment of the slots 41and 43. Suitable bearing mountings 45 and 46 support the tube 42 forrotation at the front of the aggregate tank 15. Inner tube 40 alsoextends through the front of tank 15 and is fixedly connected to anupwardly extending cylindrical chamber 47. A box-like housing 48surrounds the forward end of tubes 40 and 42, the connection of lever 44to tube 42, and the lower portion of chamber 47 at its connection toinner tube 40. A peripheral slot 49 is formed in housing 48 to extendaround the upper half thereof. Slot 49 extends completely across the topof housing 48 and about half-Way down each side thereof. Lever 44 ispositioned to move in this slot as it is rotated about its pivotal axisabout tube 40. The shoulders formed by the ends of the slot 49 at therespective sides of housing 48 define the extreme limits of movement oflever 44.

As best seen in Fig. 11, the valve 37 which controls the flow of air todrive air pipe 38 is controlled by a plunger 50 which extends upwardlybeyond the casing of valve 37. Plunger 50 is biased upwardly by springmeans (not shown) in valve 37 tending to maintain the valve closed andprevent the fiow of air to drive air pipe 38. 'A U-shaped bracket 51 issecured to the valve casing and has two spaced u standing arms 52, 53extending thereabove. A lever 54 is pivoted on arm 52 and is formed witha head 55 p sitioned to bear against the to of plunger 50. Arm 53pivotally carries a lever 56 which has one arm 57 extending towardplunger 50 and has its free end positioned to overlie the head portion55 of lever 54. A coil spring 58 urges the free end of arm '57downwardly to exert downward force on the head portion 55 of lever 54and on the valve plunger 50 to open valve 37 and permit the fiow of airto drive air pi e 38. Lever 56 is also formed with an upstanding arm 59which has a cam surface 60 at its up er end located in ali nment wi hthe slot 49 in which lever 44 moves. A bracket 61 affixed to the innerside of the front wall of housing 48 pivotally su ports a bell cranklever 62 hav ing a long arm 63 which has a transverse segment 6341 atits free end overlying the lever 54 at the side of the pivotal axisthereof remote from head 55. An upstanding arm 64 of the bell cranklever is adapted to abut a ainst the inner end of a screw 65 whichadjustablv extends throu h the front wall of housing 48. The lever 62 isposi i ned such that the arm 63 forms a limit stop for lever 54 limi nthe movement of the latter (clockwise in. Fi 113 ab t its pivotal axisunder the urging of lever 56 and spring 58.

Nnrmallv. as shown in Fig. ll. lever 56 bears against the head 55 onlever 54 to maintain valve plunger 50 d wn and keep valve 37 open. Valve37 is thus maintained en as long as lever 56 is not engaged by manuallever 44 and is thus free to ssume the open position to whi h it isbiased b snring 58. The adiustment of scre 65 determines the full openposition of valve 37. and thus the amount of air which can be suppliedto the drive air c duit when valve 37 is open. o close valve 37. manualer 44 is rotated about its pivotal axis (clockwise in i 8) to assume theextreme ri ht hand position in Fi 8. Tu so moving. lever 44 bearsagainst the cam surface 60 n lever 56 nd moves lever 56 angularlvclockwise in Fig. lll to lift the lever arm 57 a ains the ur in ofspring 58. This releases the d wnward force exerted by the head 55 onlever 54 and the latter is permitted to move an ularly about its pivotaaxis (counter-clockwise in. Fig. lll. Such movement of lever 54 permitsupward movement of valve plunger 50 under its n rmal sprin bias to closevalve 37.

A best seen in Fi 13. the v lve 33 for con rollin the flow of air to aitator pipe 34 is als c ntrolled 1W the position of hand lever 44-.Valve 33 is controlled bv a plun er 66 which s normally b ased by sprinmeans (n t shownl ithin the valve to its upper position. in which valve33 s clo ed. Plunger 66 extends upwardl through the casing of valve 33.A bracket 67 secured to the casing of valve 33 pivotally supports alever 68, the latter being formed with an upstanding arm 69 and an arm70 overlying the top of plunger 66. A coil spring 71 urges lever 69 toassume a normal position in which lever arm 70 does not exert a downwardforce on plunger 66. A cam surface 72 is formed on upstanding lever arm69 and is normally disposed in alignment with the slot 49 in housing 48in which manual lever 44 moves.

With this construction it will be apparent that valve 33 is closed atall times except when manual lever 44 is at its extreme left-handposition in Fig. 8. In moving lever 44 to that position to open valve33, the lever bears against the cam surface 72 to displace lever 68angularly about its pivotal axis (counter-clockwise in Fig. 13) toovercome the bias of its associated spring 71. The lever arm 44 in thisposition causes lever arm 70 to exert a downward force on plunger 66 andto maintain the plunger in its down position as long as lever 44 is inthis extreme position.

The water conduit 2611 leading from the outlet of valve 26 at water tank14 extends into housing 48 and is provided with a valve 73 controllingthe flow of water from conduit 26 to the outlet conduit 74. As best seenin Fig. 12, water valve 73 is under the control of a plunger 75 whichextends outwardly beyond the valve casing. By spring means (not shown)within valve 73 the plunger 75 is biased toward its outer position totend to close valve 73 and prevent the flow of water therethrough.Normally, however, this bias on plunger 75 is overcome by aspring-pressed lever arrangement which urges plunger 75 inwardly tomaintain valve 73 open at all times except when manual lever 44 is inits extreme right-hand position in Fig. 8. A bracket 76 secured to thecasing of valve 73 pivotally supports a lever 77, which has an upwardlyextending arm 78 adapted to bear against the outer end of plunger 75 andan arm 79 extending outwardly therefrom and extending across the path ofmovement of manual lever 44. A coil spring 80 normally urges lever 77(counter-clockwise about its axis in Fig. 12) to a position in which itabuts against valve plunger 75 and forces the plunger inwardly to permitthe fiow of water through valve 73. The adjustable lever arrangement61-65 already described in connection with air valve 37 (Fig. 11) alsocooperates with lever 77 to form an adjustable limit stop therefore,with a portion of segment 63b of lever 62 overlying the lever 77 tolimit movement thereof counter-clockwise in Fig. 12. In this manner, thescrew 65 determines the position to which valve 73 can be fully openedand thus governs the rate of water flow therethrough.

Normally spring 80 urges lever 77 to a position forcing plunger 75inward to open valve 73. To close valve 73 manual lever 44 is moved toits extreme right hand position in Fig. 8. In so moving, lever 44engages and forces downwardly the free end of lever arm 79. Lever 77therefore moves angularly about its pivotal axis (clockwise in Fig. 12)against the urging of spring 78 to release the inward force on plunger75. Plunger 75 is thus permitted to assume its extreme outer position toclose water valve 73.

As shown in the drawings, cylindrical chamber 47 has a greatercross-sectional area than tube 40. so that the air pressure withinchamber 47 is less than that in tube 40. Only the relatively finelydivided particles of aggregate are carried by the air stream upwardlythrough chamber 47 and out the discharge conduit 81. Any coarse lumps ofaggregate drop to the bottom of chamber 47 where they are exposed to thehigh pressure air stream from pipe 40 and are broken up thereby. Afterbeing broken up these particles are carried by the air stream upwardlythrough chamber 47 to the discharge outlet 81.

The outlet conduit 81 from chamber 47 leads to a swivel connection 82 towhich is affixed a hose 83 leading to the discharge gun for theaggregate. Also affixed to conduit 81 is a conduit 84 which at its otherend is connected to a coupling 85, which communicates with air conduit29. Conduit 84 serves as a booster air supply line to assist the flow ofaggregate through hose 83.

The air supply to coupling 85 also is in communication with a hose 86which leads to the operators mask, for a purpose which will appearhereinafter. A manually controlled valve 87 is positioned to control theair supply to hose 86.

Gage 88 communicates through conduit 89 with the dnve air conduit 38 toindicate the air pressure therein,

8 conduit 89 being joined to the drive air conduit 38 at the Outlet sideof valve 37.

Feed gage r 90 indicates the airpressure within aggregate tank 15 'byway of a conduit .91 whichextends'iinto the aggregate tank and isconnected at its upper end with a screen cap 92. Screen cap 92 is f=finemesh construction preventing the entry'of aggregate into conduit 91."The air pressure within the aggregate tank is,.o f course, due --to thefeed .air entering the tank at ports '35, so that gage 90 :is responsiveto the feed air -pressure 'in conduit 341 Therefore, the :feed a'irsupply' is regulated in accordance with the reading of gage 90.

At the gun, where the ag regate and water streams are mixed and sprayedonto t e surface-to be coated, the water conduit, in the form'of a'flexible hose 74g connected'to conduit 74, terminates at the inlet of-a-'-valve body-93. A valve member-within valve body 93 is controlled bythe position of plunger 94 to control the passage of water between base74;: and a flexible outlet hose 95 at the outlet 'of :valve 93. Bymeansof ;a rod 96 and a bracket 97 rigidly interconnecting rod 9 6 and valveplunger 94, handle "98 isadapted to control the operation of valve =93.Handle 98 -is'=rotatably mountedfwithin a bushing 98a andat its upperend carries apin' 98b, which '18 positioned eccentrically with respectto the axis of rotationof handle 98. Red 596 carries a ring =96a yvhichsurrounds pin 98b. With this arrangement the angular position ofhandle-98 with respect to bushing98a.controls the position of .pin 98b,which by its engagement -with rod 96 controls -thevalve-within valvejbody- 93.

Water hose 95 extends in a loop from the top 'ofyalve .body 93 to aninlet 100 formedin a coupling l01. 'Another inlet to coupling 101receives the flow aggregate :from hose 83. Preferably hose 8 3 isconnected to coupling 101 by .a swivel connection, so that to eliminatea Ztwistlor kink in hose 83 the entire gunassembly does not 113N610 :bemanipulated. A flexible'hose 102 is connected to the outlet of coupling101 and serves to mix the -respective streams of yvater and aggregate.The mixed water and aggregate are then sprayed from the outlet nozzle ofhose 102 onto the surface to be coated. The shape of discharge .hose 102determines the texture of the sprayed coating. Fora coarse texturedcoating hose 102 should .he'straight. 'For a tine textured coatin'g hose#102 should be looped to insurea more intimate ,rnixture of the waterand aggregate. An upstanding bracket member 103 rigidly interconnectsthe bushing 98a, valve body 93 and coupling 101. A standard104 rigidlyconnected to bracket 103 and extending thereabove supports a lamp 105anda microphone 106. An electrical ,cable 106a for the microphone andthe lamp extends along the unitary hose assembly 107 from the truck tothe gun. The lamp 104 assists the operator in seeing the surface to becoated, while the microphone permits instantaneous communication betweenthe operator of the spray gun and the assistant at the truck.

As best seen in Fig. 1, the operator wears protective clothing,including a face mask to prevent his breathing in the 'dust and sprayfrom the gun. For this purpose the air hose 86 is connected to acoupling 108, to which is also connecteda flexible ho'se 109 leading toa nose mask 110 Worn by the operator (Fig. 4). A regulator valve.within'coupling 108 is controlled manually by knob 111 to regulate theair pressure in hose 109. A portion of hose 109 is physically supportedby the belt of a harness 112 worn by the operator. This 'air supply tomask 110 assures the operator an adequate supply of fresh air forbreathing, and, by exerting a positive air pressure from within themask, prevents the entry .of dust ,or other particles into the mask.

The unitary hose assembly. 107 includes the aggregate hose 83, waterhose 74a, air hose 86 and electrical con- When coating interiorwalls,such as 'basementwalls, it is preferable to locate an exhaust fan;indicated at 113 in Fig. 1, in one of the windowsto exhaust the dustfrom the roomheing sprayed.

In using the present invention, the truck carries all of the componentsthereof to the siteof the spray peration. The air compressor 13,airstorage-tank 12, water :tank 14, aggregate tank 15, and the controlvalve assembly Within housing 48 are alljsuppqrted by the truck name 11.'The air,,vvater'a nd cement heses'lead- 'ing to the spray gunareconven'iently looped "around initiation .or a stream of .air throughtzbraekets 1 14,4135 whichyproject outwardly frgm tank 15; "The spray(gun, operators h'arness, -air-inask, protective clothing, and theexhaust fan 113 are alsojcarried on the truck. Theentiresupply=of-waterand-cement iused'at the ."job arecarried within therespective tanks.

.An air release valve 116 is provided at the top of'the aggregategtankand may be manuallyopened -to release the air under pressuretherein after the spraying job 'ghas been completed.

,Except whensthespray-gun is to be operated,control lever 44 is inthe-extreme right-hand position Fig."-8 -so-that there is .no' :air:supplied to the feed-air conduit 84,within theaggregatertank,:no:air'supplied to the drive air.con duit 73'8, mocement :aggregate 'beeing supplied to hose @8'3, and :no waterv supplied*to hose 74a.

T0 condition the system .-'for operation of -the spray gun .the :lever.144 ris moved away from I its extreme righthand position in Fig. r8. Asthe lever moves out of engagement :withilever 56, valve 37 opens--fully-'to-supply .air to the drive air.conduit 38. When valveinitially.opens, .the sleeve valve 3 9;controlling:the entryiof cement aggregateinto the hose 83 is still closed, as are the respective :valves 63 and.73 controlling the supply of air :-to the feed air :conduit 34 and :thewater hose 7411. "Thus, the only result of initial opening movement of:lever .44 is to direct. a streamI-of air into pipe 40 and thence tozhose 83.

.As 'lever .44.tmoves away from its extreme right-hand :position .inFig. '8 .it releases lever-'77 and :permits'valve ,to .open .and supply.waterto water :hose 74a.

Astangular movement of lever .44 is continued (counterclockwise in Fig.8) the outer tube 42 rotates about tube \40.; so' that slot .43approaches alignment with -slot A1, o that sleeve valve 39 gradually isopened. The 'fact thatopening of the sleeve :valve -'is preceded by thetube 40 from drive air conduit 38, and the gradualopening of sleeve-valve 39, \prevent clogging :of the aggregate ;'hose with cement.

:When thezlever A4 reaches :its extreme -left hand posi- .,tion;in Fig.8, .it.-engages lever 68at 72;.andopens-valve ;33 gradually to.supplyair to feed air conduit 3'4. This zfiir supply escapes throughholes'35 'to discharge a plurality of upwardly and' inwardly directedair jets into therbqttom of tank .15. These air jets act against theaggregate in the bottom of tank :15 and 'force it into the .elongatedhole in sleeve valve 39, WhQSC slots 41 and Aaare fully in register aslever.'44'contacts the lever por- .tion :72. "The aggregate at thebottom of tank 1'5 is in the formof finely divided sand-and cementbecause of the agitating action of the air jets emerging 'from the holes.35, vso vthat a finely :divided dry :rnixture enters ,tube 40. Thedrive air stream from conduit 38-pushes the aggregate streama'long tube40, upwardi-in c'hamber .47, into hose 83. A booster air stream 'fromhose 84 provides additional pneumatic pressure to sustain the How ,ofaggregate through the hose 83.

j At-the spray gun the =water stream in'hose 74a ismixed into the streamof dry aggregate from :hose 83,-;under the contro'i of the mixing valve93 operated by 'hand le The operator holds handle 98 with one hand and=with his other hand controls the shape and direction of discharge hose)102 :to direct .thewet mixture onto the surface "being coated. Becauseof the .even how of dry aggregate through hose .83 and because of .theconvenient arrangement of the spray gun assembly the gun operatorsstrengthis not taxed in the operation of the :present gmvention.

Air is supplied through hose 86 to the .operators :face mask to protecthim irom dust resulting firorn thespray operation. i

To adjust the relative proportions .of Water in hose 744 an drive air inconduit 38 'yvithrespect ztQ'ifeed air in conduit ;34 the screw 65 .maybe adjusted intor out, he eby vary g t a r an d e i flows in thetull,open position of their respective ,valves. This adjustment insure smc hflow p e y a g g te throu hihese $3 and ,a more accurately controlledmixing of water andaggregate at the spray gun.

"Upon completion of the "spraying job, the lever 44 is moved in theopposite direction (clockwise infFig. 8) to ts extreme ight-ha p o Thisa ion closes valve ,33 to shu off th e irsupplY to condui .3 9 05.65 seev va e 3. to. p v n th l the fl -d r ag egate out at t nk .1 c oses vave .73 toshut on the Water su ply o 1. 9 44; andfina y closes" valve 137to shut bit the drive air suppiy'to conduit 38. The release tank adaptedfor dry cement aggregate,

'7 valve 116 for the aggregate tank is opened manually gust before lever44 has reached its extreme right-hand position.

While there has been described herein a specific embodiment of theinvention it is to be understood that various modifications andvariations of the described form may be resorted to without departingfrom the spirit and scope of the invention.

We claim:

1. In apparatus for applying a cement coating, a unitary transportableassembly comprising an air compressor, a compressed air storage tank, awater tank, condu it means connecting said air storage tank to the topof said water tank to pressurize the water therein, a tank containing anaggregate of dry cement, pneumatic means for effecting the flow ofmaterial from said aggregate tank, valve means controlling the flow ofair from said air compressor tank to said pneumatic means, valve meanscontrolling the flow of water from said water tank to an outlet hose,and valve means controlling the flow of dry lcgement aggregate from saidaggregate tank to an outlet ose.

2. In apparatus for applying a cement coating, a unitary transportableassembly comprising an air compressor, an air storage tank, a watertank, a tank containing an aggregate of dry cement, valve meanscontrolling the flow of dry cement aggregate from said aggregate tank toan outlet hose, valve means controlling the flow of compressed air fromsaid air tank to said outlet hose, valve means controlling the flow ofwater to another outlet hose, and a single control lever operative tocontrol each said valve means.

3. In apparatus for applying a cement coating, in combination, acompressed air conduit, a valve controlling the flow of air through saidconduit, a tank containing an aggregate of dry cement, a valve operativewhen open to permit the flow of dry cement aggregate out of said tank,means operative when said last-mentioned valve is open to effect a flowof dry cement aggregate out of said tank into said flowing stream ofcompressed air, and a single movable control means operative to open thevalve for the air conduit and the valve controlling the flow of drycement aggregate out of the tank.

4. In apparatus for applying a cement coating, in combination, acompressed air conduit, a valve controlling the flow of air through saidconduit, a tank containing an aggregate of dry cement, a valvecommunicating with said tank and operative when open to permit the flowof dry cement aggregate out of said tank, a water conduit, a valvecontrolling the flow of water through said water conduit, meansoperative when said valve communicating with the aggregate tank is opento effect a flow of dry cement aggregate out of said tank in response tothe flow of compressed air through its conduit, and a single unitarycontrol means operative to open the valve communicating with theaggregate tank and the air and water valves.

5. In apparatus for applying a cement coating, a tank containing anaggregate of dry cement, a first tube fixedly positioned in said tankand formed with a longitudinal slot along its bottom, a second tubesnugly rotatably mounted about said first tube contiguous therewith andformed with a longitudinal slot aligned with the longitudinal slot inthe first tube at a predetermined angular position of the second tube,said first tube when the respective slots therein are so alignedcommunicating with the interior of said tank, an outlet conduitconnected to said first tube, and means for effecting a flow ofcompressed air in said tank upwardly toward said tubes to forceaggregate from said tank into said first tube for passage to said outletconduit when said slots are so aligned.

6. In apparatus for applying a cement coating, a storage a first conduitof predetermined cross-section communicating with said tank, means foreffecting a flow of dry cement aggregate and compressed air through saidfirst conduit, a device for breaking lumps in the dry cement aggregateflowing through said first conduit comprising a chamber attached at thedischarge end of said first conduit and extending upwardly andtransversely thereof to provide a chamber wall opposite the dischargeend of said first conduit for impingement thereagainst of aggregateentering the chamber, said chamber having a larger cross-sectional areathan said conduit to reduce the velocity of the air-aggregate streamflowing therethrough from said first conduit, and

a discharge conduit communicating with said chamber .therethrough, avalve and connected thereto at a point disposed above the connection ofsaid first conduit thereto for conveying the stream of air and aggregatefrom the chamber.

7. Apparatus for applying a cement coating which comprises a tankcontaining an aggregate of dry cement, a valve communicating with saidtank and operative when open to permit the flow of dry cement aggregateout of said tank, means for discharging compressed air within said tankto force said aggregate through said aggregate valve when the latter isopen, a valve controlling said compressed air discharge, an outletconduit for said cement aggregate connected to said aggregate valve,means for effecting a flowing stream of compressed air through saidoutlet conduit to move said aggregate controlling said air stream, meansfor effecting a flow of water through another conduit, a valvecontrolling said water stream, and a single lever operable in onedirection to sequentially open said water valve, said air stream valve,said aggregate valve and said compressed air discharge valve andoperable in the other direction to sequentially close said valves in theinverse order in which they were opened.

8. Apparatus as in claim 7 further characterized by means for adjustingsaid air stream valve and said water valve to control the respectiveflows therethrough rela* tive to the flow of compressed air through saidcompressed air discharge valve into the aggregate tank.

9. Apparatus for applying a cement coating which comprises a source ofdry cement aggregate, an aggregate hose, means for effecting a flow ofair through said hose, means for directing air under pressure in theform of a plurality of jets against said aggregate to thoroughly mix theaggregate and push it into said flowing air stream which passes throughthe aggregate hose, a water hose, means for effecting a flowing streamof water through said water hose, means for introducing said stream ofwater into said flowing stream of dry cement aggregate, and means forspraying the resultant stream of wet cement onto the surface to becoated.

10. In an apparatus for applying a cement coating,

-a tank adapted to contain an aggregate of dry cement,

a tubular member disposed horizontally in said tank above the bottomthereof, said member having an inlet opening in the lower portionthereof and an outlet opening on one endthereof, a perforate conduitdisposed in said tank below the member, means for supplying air to saidperforate conduit to thereby feed aggregate to said inlet opening, andconduit means extending into said tubular member for directing a streamof air longitudinally of said member towards the outlet opening thereinto thereby induce the fiow of material through said member.

11. The combination of claim 10 including a vertical chamber having across-sectional area greater than said tubular member, said member atthe outlet end thereof communicating with the lower end of said chamber,and a discharge conduit communicating with the upper end of saidchamber.

12. The combination of claim 11 including means connected to saiddischarge conduit adjacent said cham' her for directing a stream of airinto said discharge conduit to aid the flow of aggregate therethrough.

13. In an apparatus for applying a cement coating, a tank adapted toreceive an aggregate of dry cement, a tubular member disposedhorizontally in said tank above the bottom thereof, said member havingan inlet opening in the lower portion thereof and an outlet opening inone end thereof, a U-shaped perforate conduit disposed in said tankbelow said member with the legs of said U-shaped conduit parallelingsaid member, means for applying air under pressure to said conduit toagitate the aggregate in the tank and feed aggregate to said inletopening, an eductor conduit extending into said tubular member fordirecting a stream of air longitudinally thereof towards the outletopening therein, and means for supplying pressurized air to said eductorconduit to drive the material through said member.

14. The combination of claim 13 wherein said opening in said tubularmember comprises a slot extending longitudinally thereof.

15. In an apparatus for applying a cement coating, a tank adapted toreceive dry cement aggregate, a tubular member disposed horizontally insaid tank above the bottom thereof and having one end extending throughsaid tank, said tubular member having an opening in.

the lower portion thereof, a U-shaped perforate conduit disposed in saidtank below said member, the legs of said U-shaped conduit extendingoutwardly of said tank, a closure plug removably mounted on one of theoutwardly extending legs of said conduit, means for applying air underpressure to one of the legs of said conduit to cause air to flow throughthe perforations therein and feed aggregate to said member, and meansfor effecting the fiow of aggregate through said member.

16. In an apparatus for applying a cement coating, a tank adapted tocontain an aggregate of dry cement, a tubular member in said tank abovethe bottom thereof and having one end extending outwardly of said tank,said tubular member having an opening therein, a drive air conduithaving one end extending into said tubular member to direct a stream ofair longitudinally thereof towards the outwardly extending end of saidmember, valve means on the other end of said drive air conduit forcontrolling the flow of air therethrough, a feed air conduit in saidtank below said member and having a plurality of apertures therein, andvalve means external of said tank for controlling the flow of air tosaid feed air conduit.

17. In an apparatus for applying a cement coating, a tank adapted tocontain an aggregate of dry cement, a tubular member in said tank abovethe bottom thereof and having one end extending outwardly of said tank,said tubular member having an opening therein, a drive air conduithaving one end extending into said tubular member to direct a stream ofair longitudinally thereof towards the outwardly extending end of saidmember, valve means on the other end of said drive air conduit forcontrolling the flow of air therethrough, a feed air conduit in saidtank below said member and having a plurality of apertures therein,valve means external of said tank for controlling the flow of air tosaid feed air conduit, and a single control lever operable in onedirection to sequentially open said drive air valve means and said feedair valve means and operable in the opposite direction to close thevalves in the inverse order of opening thereof.

18. The combination of claim 17 wherein said control lever is pivotallymounted on the outwardly extending end of said tubular member.

19. The combination of claim 17 including a sleeve mounted on saidtubular member and having an opening therein adapted to register withthe opening in said tubular member in a predetermined angular positionof said sleeve, said lever being mounted on said sleeve to rotate saidsleeve in response to operation of said lever to open and close saidvalve means.

20. The combination of claim 17 including cam means engageable by saidlever for controllably opening said feed air valve means in accordancewith the position of said lever, and means for independently adjustingthe flow through said drive air valve means when the latter is opened bysaid lever.

References Cited in the file of this patent UNITED STATES PATENTS998,762 Faller July 25, 1911 2,261,441 Layne Nov. 4, 1941 2,495,540Nichols Jan. 24, 1950 2,543,517 Anderson Feb. 27, 1951 2,577,664 ProDec. 4, 1951 FOREIGN PATENTS 614,282 Germany June 5, 1935

